This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 9 |
| 7 | 26 |
| 8 | 299 |
| 9 | 1183 |
| 10 | 10700 |
| 11 | 24736 |
| 12 | 349232 |
| 13 | 626053 |
| 14 | 6680953 |
| 15 | 26364609 |
| 16 | 137246955 |
| 17 | 353304459 |
| 18 | 4826416835 |
| 19 | 8199440662 |
| 20 | 93679518802 |
| 21 | 315943737305 |
| 22 | 1913783049725 |
| 23 | 4382586624256 |
| 24 | 60629067426943 |